Experimental investigation on the effectiveness of laminated rubber bearings to isolate metro generated vibration

Vibration control is important in maintaining the functionality of the buildings surrounding a metro. Among the many methods of vibration control, track isolation is by far the most efficient approach. However, for buildings constructed near a metro line which has no track isolation, base isolation of the building structures is useful to alleviate metro generated vibration. Laminated rubber bearings are commonly used for seismic isolation of building structures; however, their effectiveness in isolating metro generated vibration has not yet been well explored. In this study, scaled model tests were carried out to investigate the isolation effectiveness of laminated rubber bearings in base isolated building structures. Specifically, four types of laminated rubber bearings, i.e. thick natural rubber bearings, thin natural rubber bearings, thick high damping rubber bearings, and thin high damping rubber bearings, were tested. Tests were carried out under the designed compressive stress, 70% of the design compressive stress and at various excitation intensities. Our results show that the isolation effectiveness of both thick natural rubber bearings and thick high damping rubber bearings were significant and stable, while thin rubber bearings offered insignificant and unstable isolation.